HDG SET knob - Depress ?

[Red Dog]

Anyone has any idea what is the purpose of this control do?
HDG SET knob - Depress in Instrument panel category

it's declared in the F-16 key list but I don't see any effect when I assign and test it

Closest guess I can do is the pushbutton we usually find on HDG and CRS encoder for centering the heading bug.
That is not a real thing in the non EHSI equipped F-16 (but might be in the EHSI equipped airframe?)
but anyway it does not center the heading bug in the latest DCS

The CRS Set / Brightness control knob - Depress  works as advertized and enable EHSI brightness control

Anyone has any clue what the HDG SET knob - Depress does? 

 

Thanks